The Research And Assessment On The Forest Ecosystem Health In Dongqian Lake

As a new research area of forest ecology, forest health assessment has got much controversy.However study on fotest health assessment can provide scientific basis and guidelines for forest protection and sustainable forest management theoretically and practically.According the Dongqian Lake forest actual situation, this paper proposed a set of feasible,practical forest ecosystem health evaluation index system. This index system could be divided into three different classes, such as objective class, indicator class and element class, which cover four respects of forest ecosystem health: Community structure, Soil condition, Community update and Resistance power to research the forest ecology health of the Dongqian Lake.Then analyzes the related research data which obtained through the open-door community investigation and the laboratory experiment and uses the comprehensive index of health method and the health distance method to evaluate the health status of the Dongqian Lake forest, the main result is as follows:(1) From the four aspects of community structure, Soil condition, Community update and Resistance power, in all kinds plots there is a variety of community structure in different, what the community structure is best is the dz plot, the community structure value of ms2 (brush) plot is smallest, artificial economic forest ty plot's community structure value is also small, This shows that the natural forests in the community structure to be better than the plantation more. The difference between every plots is not great of soil conditions. Community update in yd2 plot is better than the other plots, the minimum value of community update is ty plot, almost no update of existence.In the resistance power, there are litter human interference to all sorts of plots, fewer pests and diseases, but because of the region for more than a pine forest, there are potential pest crisis in artificial afforestation, the transformation should be reasonable, and optimize the allocation of community .(2) The health composite index distributes between 0.66-0.2, the mean value is 0.4, from high to low is: plot dz> plot bs3> plot bs2> plot sj1 > plot xs> plot ly> plot sj2> plot yd1> plot yd2> plot bs1> plot ms1> plot bj> plot ms2> plot ty> plot sg. In 15 plots, on forest ecosystem healthy rank division standard, there are 7 plots be in unhealthy (plot sg, ty, bj, ms2, ms1, sj2, yd2), 7 plots be in sub-healthy(plot bs1, ly, sj1, xs, yd1, bs2, bs3), 1 plot be in healthy (plot dz), forest health degree of Dongqian Lake forest is not high.(3) Using two different assessment methods (the comprehensive index of health method and the health distance method) to evaluated on the forest of Dongqian Lake, then obtained two group of forest healthy indexs.Comparated and analysised these two groups of health indexs, the conclusion is that the two groups of forest healthy indexs is not obvious difference, health standard tendency tended to be consistent in all plots.The index of health distance method is higher than the comprehensive index of health method generally, because processing of two method differently result in the overall deviation.(4) All 15 plots, there are 10 plots dealed with by inserting plants, the average health composite index is 0.42; There are 4 plots dealed with by cleaning up plants, the average health composite index is 0.31, including a artificial economic plot, its health composite index is 0.22; There are 1 plot not undergone manual dealed with, its average health composite index is 0.66. The evaluation results indicated that between the different processing methods, the health composite index which plots of dealed with by inserting plants is higher than that of by cleaning up plants as a whole.The evaluation results showed that majority of plots are in the state of health or sub-health, the evaluation results tally with actual situation of Dongqianhu forest. Based on the results of the final papers, fanally we discuss on how to establish a set of practical forest health evaluation index system and then give some advices and put forward some research direction.